warning light MERCEDES-BENZ A-CLASS HATCHBACK 2012 Workshop Manual

Releasing
X Pull handle :.
The red !indicator lamp in the instru-
ment cluster goes out.
i You can only release the electric parking
brake when the key is in position 1or 2in
the ignition lock.
Applying automatically The electric parking brake is applied auto-
matically:
R if DISTRONIC PLUS brings the vehicle to a
standstill (vehicles with automatic trans-
mission) or
R if the HOLD function is keeping the vehicle
stationary.
In addition, at least one of the following con-
ditions must be fulfilled:
R the engine is switched off
R the driver's door is open and the seat belt is
not fastened
R there is a system malfunction
R the power supply is insufficient
R the vehicle is stationary for a lengthy
period.
The red !indicator lamp in the instrument
cluster lights up.
i The electric parking brake is not automat-
ically applied if the engine is switched off by
the ECO start/stop function.
Releasing automatically i
The electric parking brake can only be
released automatically in vehicles with
automatic transmission.
The electric parking brake of your vehicle is
released automatically when all of the follow- ing conditions are fulfilled:
R the engine is running.
R the transmission is in position Dor R.
R the seat belt is fastened.
R you depress the accelerator pedal. If the transmission is in position
R, the tailgate
must be closed.
If your seat belt is not fastened, the following conditions must be fulfilled to automatically
release the electric parking brake:
R the driver's door is closed.
R you have shifted out of transmission posi-
tion Por you have previously driven faster
than 3km/h.
Emergency braking The vehicle can also be braked during an
emergency using the electric parking brake.
X While driving, push handle :of the electric
parking brake (Y page 163).
i The vehicle is braked for as long as han-
dle :of the electric parking brake
pressed. The longer the electric parking
brake handle :is depressed, the greater
the braking force.
During braking:
R a warning tone sounds
R the Release parking brake Release parking brake message
appears
R the red !indicator lamp in the instru-
ment cluster flashes
When the vehicle has been braked to a stand- still, the electric parking brake is engaged. Parking up the vehicle
If you leave the vehicle parked up for longer
than four weeks, the battery may be damaged by exhaustive discharging.
If you leave the vehicle parked up for longer
than six weeks, the vehicle may suffer dam-
age as a result of lack of use.
X Visit a qualified specialist workshop and
seek advice.
i You can obtain information about trickle
chargers from a qualified specialist work-
shop. 164
ParkingDriving an
d parking

dynamic changes in the bars at the start of
a journey. During a prolonged driving time,these changes are smaller. For more
dynamic changes, perform a manual reset.
For further information on the ECO display,
see (Y page 212). Braking
Important safety notes G
WARNING
If you shift down on a slippery road surface in an attempt to increase the engine's braking
effect, the drive wheels could lose their grip.
This increases the risk of skidding and having
an accident.
Do not shift down for additional engine brak-
ing on a slippery road surface.
Downhill gradients Change into a lower gear in good time on long
and steep downhill gradients. Take particular note of this when driving a laden vehicle and
when towing a trailer. For vehicles with auto-
matic transmission, you need to have selec-
ted manual drive program M(Ypage 156).
i This also applies if you have activated
cruise control, SPEEDTRONIC or DIS-
TRONIC PLUS.
This will use the braking effect of the engine,
so less braking will be required to prevent the
vehicle from gaining speed. This relieves the
load on the brake system and prevents the
brakes from overheating and wearing too
quickly.
i Briefly depressing the accelerator pedal
on downhill gradients while the manual
drive program Mis temporarily activated
(vehicles with automatic transmission): the
automatic transmission may switch back to the last active automatic drive program Eor
S. The automatic transmission may shift to a higher gear. This can reduce the engine's
braking effect.
Heavy and light loads G
WARNING
The braking system can overheat if you leave your foot on the brake pedal while driving.
This increases the braking distance and could
even cause the braking system to fail. There is
a risk of an accident.
Never use the brake pedal as a footrest. Do
not simultaneously depress both the brake
pedal and the accelerator pedal while driving.
! Depressing the brake pedal constantly
results in excessive and premature wear to
the brake pads.
If heavy demands are made on the brakes, do not park the vehicle immediately. Drive on for
a short while. This allows the airflow to cool
the brakes more quickly.
If the brakes have been used only moderately,
you should occasionally test their effective-
ness. To do this, brake more firmly from a
higher speed, paying attention to traffic con-
ditions. This improves the grip of the brakes.
Wet road surfaces If you have driven for a long time in heavy rain
without braking, there may be a delayed reac-
tion from the brakes when braking for the first time. This may also occur after a car wash orafter driving through deep water.
You have to depress the brake pedal more
firmly. Maintain a greater distance from the
vehicle in front.
After driving on a wet road or having the vehi-
cle washed, brake firmly while paying atten-
tion to the traffic conditions. This will warm up
the brake discs, thereby drying them more
quickly and protecting them against corro-
sion. 166
Driving tipsDriving and parking

Storing the current speed and calling up
the last stored speed G
WARNING
If you call up a stored speed and this is dif-
ferent from the current speed, the vehicle
accelerates or brakes. If you do not know
what the stored speed is, the vehicle may
accelerate or brake unexpectedly. There is a
risk of an accident.
Take the traffic conditions into account
before calling up the stored speed. If you do
not know what the stored speed is, store the
desired speed again.
X Briefly pull the cruise control lever towards
you =.
X Remove your foot from the accelerator
pedal.
The first time cruise control is activated, it
stores the current speed or regulates the
speed of the vehicle to the previously
stored speed.
Setting a speed Keep in mind that it may take a brief moment
until the vehicle has accelerated or braked to the set speed.
X Press the cruise control lever up :for a
higher speed or down ?for a lower speed.
X Keep the cruise control lever pressed until
the desired speed is reached.
X Release the cruise control lever.
The new speed is stored.
X To adjust the set speed in 1 km/h incre-
ments: briefly press the cruise control
lever up :or down ?to the pressure
point.
The last stored speed increases or decrea-
ses in 1 km/h increments.
X To adjust the set speed in 10 km/h
increments: press the cruise control lever
briefly up :or down ?beyond the pres-
sure point.
The last stored speed increases or decrea- ses in 10 km/h increments. i
Cruise control is not deactivated if you
depress the accelerator pedal. For exam-
ple, if you accelerate briefly to overtake,
cruise control adjusts the vehicle's speed
to the last speed stored after you have fin- ished overtaking.
Deactivating cruise control There are several ways to deactivate cruise
control:
X Briefly press the cruise control lever for-
wards B.
or
X Brake
or X Briefly press the cruise control lever in the
direction of arrow A.
Variable SPEEDTRONIC is selected. LIM
indicator lamp ;in the cruise control lever
lights up.
Cruise control is automatically deactivated if: R you engage the electric parking brake.
R you are driving at less than 30 km/h.
R ESP ®
intervenes or you deactivate ESP ®
R while driving a vehicle with manual trans-
mission, you shift into neutral or depress
the clutch pedal for longer than six sec-
onds.
R on vehicles with manual transmission, you
shift to a gear that is too high, and as a
result the engine speed is too low.
R on vehicles with automatic transmission,
you shift into position Nwhile driving.
If cruise control is deactivated, you will hear a warning tone. You will see the Cruise con‐
Cruise con‐
trol off trol off message in the multifunction dis-
play for approximately five seconds.
i The last speed stored is cleared when you
switch off the engine. 170
Driving systemsDriving and parking

Storing the current speed
You can use the cruise control lever to limit
the speed to any speed above 30 km/hw hile
the engine is running.
X Briefly press the cruise control lever up :
or down ?.
The current speed is stored. For five sec-
onds, the multifunction display shows the
stored speed, e.g. Limit 100 km/h Limit 100 km/h.
The segments in the speedometer light up
from the start of the scale up to the stored
speed.
Storing the current speed and calling up
the last stored speed G
WARNING
If you call up the stored speed and it is lower
than the current speed, the vehicle deceler-
ates. If you do not know the stored speed, the vehicle could decelerate unexpectedly. There
is a risk of an accident.
Pay attention to the road and traffic condi-
tions before calling up the stored speed. If you do not know the stored speed, store the
desired speed again.
X Briefly pull the cruise control lever towards
you =.
X To adjust the set speed in 1 km/h incre-
ments: briefly press the cruise control
lever up :to the pressure point for a
higher speed, or down ?for a lower speed.
or
X Keep the cruise control lever pressed to the
pressure point until the desired speed is
set. Press the cruise control lever up :for
a higher speed or down ?for a lower
speed.
X To adjust the set speed in 10 km/h
increments: briefly press the cruise con-
trol lever up :past the pressure point for a higher speed, or down
?for a lower
speed.
or
X Keep the cruise control lever pressed
beyond the pressure point until the desired
speed is set. Press the cruise control lever
up : for a higher speed or down ?for a
lower speed.
Deactivating variable SPEEDTRONIC
It is not possible to deactivate variable
SPEEDTRONIC by braking.
There are several ways to deactivate variable SPEEDTRONIC:
X Briefly press the cruise control lever for-
wards B.
or X Briefly press the cruise control lever in the
direction of arrow A.
LIM indicator lamp ;in the cruise control
lever goes out. Variable SPEEDTRONIC is
deactivated.
Cruise control or DISTRONIC PLUS is selec- ted.
Variable SPEEDTRONIC is automatically
deactivated if:
R you depress the accelerator pedal beyond
the pressure point (kickdown), but only if
your current speed does not differ by more
than 20 km/h from the stored speed. You
will hear a warning tone if this is the case.
R on vehicles with manual transmission, if
you shift to a higher gear and as a result, the
engine speed is too low.
i The last speed stored is cleared when you
switch off the engine.
Permanent SPEEDTRONIC You can use the on-board computer to limit
the speed permanently to a value between
160 km/h(e.g. for driving on winter tyres) and
the maximum speed (Y page 223).
Shortly before the stored speed is reached, it appears in the multifunction display. 172
Driving systemsDriving and parking

This speed can:
R be too high for a filter lane or a slip road
R be so high in the right lane that you pass
vehicles driving on the left
R be so high in the left lane that you pass
vehicles driving on the right
If there is a change of drivers, advise the new driver of the speed stored.
General notes DISTRONIC PLUS regulates the speed and
automatically helps you maintain the dis-
tance to the vehicle detected in front. DIS-
TRONIC PLUS brakes automatically so that
the set speed is not exceeded.
You must select a lower gear in good time on long and steep downhill gradients, especially if the vehicle is laden or towing a trailer. For
this, you need to have selected manual drive
program M(Ypage 166). By doing so, you will
make use of the braking effect of the engine.
This relieves the load on the brake system and prevents the brakes from overheating and
wearing too quickly.
If a slower-moving vehicle is detected in front,
DISTRONIC PLUS brakes your vehicle. It
maintains the preset distance to the vehicle in front.
If DISTRONIC PLUS detects that there is a risk of a collision, you will be warned visually and
acoustically. Without your intervention, DIS-
TRONIC PLUS cannot prevent a collision. An
intermittent warning tone will then sound and
the distance warning lamp will light up in the instrument cluster. Brake immediately to
increase the distance to the vehicle driving in
front, or take evasive action, provided it is
safe to do so.
The radar sensor system is switched off auto- matically in the vicinity of radio telescope
facilities (Y page 350).
For DISTRONIC PLUS to assist you when driv- ing, the radar sensor system must be:
R activated (Y page 223)
R operational i
In some countries you must deactivate
the radar sensor system (Y page 223).
For further information about the radar sen- sor system; see (Y page 350).
DISTRONIC PLUS is automatically deactiva-
ted if:
R you are driving slower than 25 km/h and
there is no longer a vehicle in front or
R the vehicle ahead has not been detected
If there is no vehicle in front, DISTRONIC
PLUS operates in the same way as cruise
control in the speed range between 30 km/h
and 200 km/h. If a vehicle is driving in front of
you, it operates in the speed range between
0 km/h and 200 km/h.
Do not use DISTRONIC PLUS on roads with
steep gradients.
Cruise control lever With the cruise control lever, you can operate
DISTRONIC PLUS and variable SPEED-
TRONIC.
The LIM indicator lamp on the cruise control
lever indicates which system you have selec- ted:
R LIM indicator lamp off: DISTRONIC PLUS
is selected.
R LIM indicator lamp on: variable SPEED-
TRONIC is selected. :
To store the current speed or a higher
speed
; To set the specified minimum distance
= LIM indicator lamp 174
Driving systemsDriving and parking

When DISTRONIC PLUS is activated, one or
two segments ;in the set speed range light
up.
i For design reasons, the speed displayed
in the speedometer may differ slightly from
the speed set for DISTRONIC PLUS.
If DISTRONIC PLUS detects a vehicle in front,
segments ;between speed of the vehicle in
front :and stored speed =light up. Assistance graphic in vehicles with a colour multi-
function display
: Vehicle in front, if detected
; Specified minimum distance to the vehi-
cle in front; adjustable
= Own vehicle
? DISTRONIC PLUS active (text only
appears when the cruise control lever is
actuated)
In the Assistance menu (Y page 217) of the
on-board computer, you can select the assis- tance graphic.
X Select the Distance display
Distance display function
using the on-board computer
(Y page 217).
i You will see the stored speed for approx-
imately five seconds when you activate
DISTRONIC PLUS.
Activating at the current speed/last
stored speed G
WARNING
If you call up a stored speed and this is dif-
ferent from the current speed, the vehicle
accelerates or brakes. If you do not know what the stored speed is, the vehicle may
accelerate or brake unexpectedly. There is a
risk of an accident.
Take the traffic conditions into account
before calling up the stored speed. If you do
not know what the stored speed is, store the
desired speed again.
X Briefly pull the cruise control lever
(Y page 174) towards you ?.
X Remove your foot from the accelerator
pedal.
DISTRONIC PLUS is activated. The first
time it is activated, the current speed is
stored. Otherwise, it sets the vehicle cruise
speed to the previously stored value.
Setting a speed Keep in mind that it may take a brief moment
until the vehicle has accelerated or braked to the set speed. :
To store the current speed or a higher
speed
; To store the current speed or a lower
speed
X Press the cruise control lever up :for a
higher speed or down ;for a lower speed.
X Keep the cruise control lever pressed until
the desired speed is reached.
X Release the cruise control lever.
The new speed is stored. DISTRONIC PLUS
is activated and adjusts the vehicle's speed to the new speed stored. 176
Driving systemsDriving and parking

Other vehicles changing lane
DISTRONIC PLUS has not detected the vehi-
cle cutting in yet. The distance to this vehicle will be too short.
Narrow vehicles DISTRONIC PLUS has not yet detected the
vehicle in front on the edge of the carriage-
way, because of its narrow width. The dis-
tance to the vehicle in front will be too short.
Obstructions and stationary vehicles DISTRONIC PLUS does not brake for obsta-
cles or stationary vehicles. If, for example, the detected vehicle turns a corner and reveals
an obstacle or stationary vehicle, DISTRONIC
PLUS will not brake for these.
Crossing vehicles DISTRONIC PLUS may detect vehicles that
are crossing your lane by mistake. Activating
DISTRONIC PLUS at traffic lights with cross-
ing traffic, for example, could cause your vehi-
cle to pull away unintentionally. HOLD function
Important safety notes G
WARNING
When leaving the vehicle, it can still roll away despite being braked by the HOLD function if:
R there is a malfunction in the system or in
the voltage supply
R the HOLD function is deactivated by the
accelerator pedal being depressed, e.g. by
a vehicle occupant
R the electrical system in the engine com-
partment, the battery or the fuses are tam-
pered with
R the battery is disconnected
There is a risk of an accident.
Before leaving the vehicle, always deactivate
the HOLD function and secure the vehicle
from rolling away. Driving systems
179Driving and parking Z

or a pneumatic drill, could cause PARK-
TRONIC to malfunction.
PARKTRONIC may not function correctly on
uneven terrain.
PARKTRONIC is an electronic parking aid with
ultrasonic sensors. It indicates visually and
audibly the distance between your vehicle
and an object.
PARKTRONIC is activated automatically if
you:
R switch on the ignition
R shift to position D,Ror Non vehicles with
automatic transmission
R release the electric parking brake
PARKTRONIC is deactivated at speeds above
18 km/h. It is reactivated at lower speeds.
PARKTRONIC monitors the area around your
vehicle using six sensors in the front bumper
and four sensors in the rear bumper.
Range of the sensors General notes
PARKTRONIC does not take into account
obstacles located:
R below the detection range, e.g. persons,
animals or objects
R above the detection range, e.g. overhang-
ing loads, tail sections or loading ramps of
goods vehicles :
Example: sensors in the front bumper,
left-hand side Side view
Top view
The sensors must be free of dirt, ice and
slush. Otherwise, they may not function cor-
rectly. Clean the sensors regularly, taking
care not to scratch or damage them
(Y page 294).
Front sensors Centre Approx. 100 cm
Corners Approx. 60 cm
Rear sensors
Centre Approx. 120 cm
Corners Approx. 80 cm
Minimum distance
Centre Approx. 20 cm
Corners Approx. 20 cm
If there is an obstacle within this range, the
relevant warning displays light up and a warn- ing tone sounds. If the distance falls below
the minimum, the distance may no longer be
shown. Driving systems
183Driving and parking Z

Warning displays
The warning displays show the distance
between the sensors and the obstacle. The
warning display for the front area is located
on the dashboard above the centre air vents.
The warning display for the rear area is loca-
ted on the roof lining in the rear compart-
ment. Warning display for the front area
:
Segments on the left-hand side of the
vehicle
; Segments on the right-hand side of the
vehicle
= Segments showing operational readiness
The warning display for each side of the vehi-
cle is divided into five yellow and two red seg- ments. PARKTRONIC is operational if yellow
segments showing operational readiness =
light up.
The gear lever position or the transmission
position of the automatic transmission and
the direction in which the vehicle is rolling
determine which warning display is active
when the engine is running. Manual transmission: Gear lever posi-
tion Warning display
Forwards gear
or
Neutral
Front area activated
Reverse gear, or
the vehicle is rolling
backwards Rear and front areas
activated
Automatic transmission:
Transmission
position Warning display
D
Front area activated
R,
Nor the vehicle
is rolling back-
wards Rear and front areas
activated
P
No areas activated
One or more segments light up as the vehicle
approaches an obstacle, depending on the
vehicle's distance from the obstacle.
From the:
R sixth segment onwards, you will hear an
intermittent warning tone for approx-
imately two seconds.
R seventh segment onwards, you will hear a
warning tone for approximately two sec-
onds. This indicates that you have now
reached the minimum distance. 184
Driving systemsDriving and parking

Problems with PARKTRONIC
Problem
Possible causes/consequences and
M
MSolutions Only the red segments
in the PARKTRONIC
warning displays are lit.
You also hear a warning
tone for approximately
two seconds.
PARKTRONIC is deacti-
vated after approx-
imately five seconds,
and the indicator lamp
in the PARKTRONIC
button lights up. PARKTRONIC has malfunctioned and has switched off.
X If problems persist, have PARKTRONIC checked at a qualified
specialist workshop. Only the red segments
in the PARKTRONIC
warning displays are lit.
PARKTRONIC is deacti-
vated after approx-
imately five seconds. The PARKTRONIC sensors are dirty or there is interference.
X Clean the PARKTRONIC sensors (Y page 294).
X Switch the ignition back on. The problem may be caused by an external source of radio or
ultrasound waves.
X See if PARKTRONIC functions in a different location. Active Parking Assist
Important safety notes Active Parking Assist is only an aid. It is not a
substitute for your attention to the immediate
surroundings. The responsibility for safe
manoeuvring and parking remains with you.
Make sure that there are no persons, animals
or objects in range while manoeuvring and
parking. G
WARNING
The vehicle will veer out when parking and can take you onto sections of the oncoming lane.As a result, you may collide with other road
users. There is a risk of an accident.
When parking, pay attention to other road
users. Stop the vehicle if necessary or cancel
the Active Parking Assist parking procedure.
! If unavoidable, you should drive over
obstacles such as kerbs slowly and not at a sharp angle. Otherwise, you may damage
the wheels or tyres.
Active Parking Assist may also display spaces not suitable for parking, e.g.:
R parking or stopping prohibitions
R in front of driveways or entrances and exits
R unsuitable surfaces
Parking tips:
R on narrow roads, drive as closely as possi-
ble past the parking space.
R parking spaces that are littered, overgrown
or partially occupied by trailer drawbars
might be identified incorrectly or not at all.
R snowfall or heavy rain may lead to a parking
space being measured inaccurately.
R pay attention to the PARKTRONIC
(Y page 184) warning messages during the
parking procedure. 186
Driving systemsDriving and parking